Pressure vessel and support



0a, 16, 1945. P, ls HAL 2,387,024

PRESSURE VESSEL AND-SUPPORT Filed Au 14, 1944 s Sheets-Sheet 1 Fig.1

Invaders: Panrick D. Hishon Wifliam D. c'ari'er Hzrberf L. Box-charsThomas N. Ravn Oct. 16, 1945. P, D H H 'N m 2,387,024

PRESSURE VESSEL AND SUPPORT.

- Filed Aug. 14, 1944 Sheets-Sheet 2 |s\ A my: 97 8 l4 Fig.11

lnvzniors: Pafrick D- Hishon William D. Caz-fer Hcrbzrr L. BorchzssThomas N. Ravn Patents at. is, rss

i s sronr Patriots D. shon, William E. Carter, and The I N. Ram,Berkeley, San imp, ni yclopment and Herbert L. archers, assitmo to ShahBeompany, San oiseo, Calm, a corporation of Dela Application August M,19%, Serial No. 5%9At8 12 Clai. ($1. 23-296) The present inventionrelates to pressure vessels and more particularly to an improvedautoslave and means for supporting the same.

In the various chemical and related industries, inresearch laboratoriesand the like, pressure vessels are often required in which the reactionsand behavior of materials under advanced prespressures often utilized incarrying out operations of these general types, the equipment employed,particularly the reaction vessel or autoclave, has conventionally beenexceedingly cumbersome and heavy, necessitating several operators tocharge ordischarge the same and un-' duly long periods of time to sealthe vessel after charging the same.

It is an object of the present invention to provide an improvedautoclave assembly which is readily and easily charged and discharged.Another object is to provide an autoclave assembly in which theautoclave may be easily and readily tilted for cleaning or otheroperations. A further object is to provide an autoclave assemblyembodying an improved autoclave closure wherein the closure securingelements are under compression load only. A still further object is toprovide an autoclave assembly with improved drainage means for theautoclave vessel. Another object is to provide an autoclave assemblywith readily demountable external heating means and independentlymounted internal heating means. Still another object is to provideanautoclave with efficient externally driven agitating means, improvedmeans for sealing the agitator shaft against the pressure withinthe-system, improved invention, will become apparent in the followingdetailed description thereof, taken together with the accompanyingdrawings forming a part oi the specification, and wherein:

in e I with the autoclave in towered and tilted position;

Figure m is a sectional elevation of the autoslave unit shown in FiguresI and II at 8.

--ferring particularly to Figures I and II, a

' base member i is provided with a column flange 32 supporting anupright tubular column member 2. Carriage member 3 is slidably mountedon column member 2 and is provided with guide collars t and 5 whichslidably engage guide rod t which is also supported by column flange t2and extends upwardly parallel to column memher 2. Clamp ring I isrigidly mounted on column member 2 near the upper end thereof and limitsthe maximum upward travel of carriage member 3. The upper end of guiderod 6 is rigidly positioned and secured by clam ring 1. Drive supporttil is rigidly mounted on the upper end of column member 2 and isprovided on one side with motor mounting 3i whichsupports drive motor21, which is of the variable speed typeand controlled through controlbox 28 mounted thereon. Electric power is supplied motor 27 throughcable 29. On the opposite side of column member 2, drive support 3|)supports bearing housing 22, agitator shalt housing ii and retainer ringit, agitator shaft i9 passing through these elements and terminatingabove bearing housing 22. An agitator 20 is mounted on the lower end ofagitator shalt i9 and a pulley wheel 28 is mounted on the upper endthereof. A second pulley wheel 24 is mounted on the drive shaft of motor2l and drives pulley wheel 23 and agitator shaft it through driveriagemember 8 and supports autoclave unit 8 which is pivotally and oilcentermounted on support bracket 97 at 9. I

counterbalance weight it is supported within column member 2 by means ofroller chain Ii Figure I is an elevation, partly in section. of

an autoclave assembly'accordingtothe invention, with the autoclave in'raised and sealed position:

Figureflis an elevation of the assembly shown which engages and passesover cog wheel I? mounted atthe upper end of column member 2. Theopposite end of roller chain ii is attached 'to autoclave unit 8 bymeans oi bracket it, the

7 bolts as at M passingthrough jacket flange dd and engaging ring memberit which is rigidly en-- sages autoclave 38 at ti, a plurality ofthreaded mounted on the outer shell 42 of the heating jacket. Innershell 43 of the heating jacket is spaced from outer shell 42 by means ofa plurality of spacer screws 82 which pass through ring member 8| inthreaded engagement therewith, through outer shell 42 and urge againstinner shell 43. Flange 19, formed of thermally insulating material, isdisposed between jacket flange 40 and ring member 8| and also serves asa spacer between jacket flange 40 and the heating jacket. Bracket I4 isrigidly attached to ring member BI and outer shell 42 of the heatingJacket. Inner shell 43 and outer shell 42 of the heating Jacket arerigidly attached to sleeve element 83 at their lower ends and spacedfrom discharge outlet 50 of autoclave 33 by means of spacer washers asat 48 which are formed of thermally insulating material and are slidableElectric power is supplied to heating elements as vat 41 by .means ofelectric cable H which passes through insulator 49 in the heatingjacket. Electric cable l1 also leads to control box 5 mounted oncarriage member 3 and is supplied current by cable l8 leading from asource of electric energy (Figure II) The autoclave bottom closure anddrain com-' prises a bushing 5| threadedly mounted in discharge outletnipple 35 being formed as a partof bushing 5| and extending upwardly indischarge outlet as shown. Bushing 32 is threadedly mounted in the endof nipple and supports a multi-disc edge type filter 34, groovedadiustment rod 53 passing through filter 54 and bushing 52 andterminating in nipple 85. Head 81 of rod 53 presses against the top offilter 54 and coil spring 33 contacting the bottom of bushing 52 and anut 33 threaded on the bottom of rod 53 urges the rod downwardly.compression forces exerted on the discs of the filter may be adiusted byadjustment of nut 83. The filter arrangement may be removed. from thedischarge outlet as a'unit by removal of bushing 5|, since the otherelements of the unit are all either. directly or indirectly supportedthereby.

The lower end of agitator shaft housing 2| is shaped to fit closely in asocket Joint with an annular shoulder formed on the inside of autoclave"near the upper end thereof at 39, the shaft housing thus forming theprimary closure for the autoclave. An annular corrugated gasket 31,preferably formed of soft steel or other deformable metal, is providedin an annular channel formed in the body of autoclave 33 and shafthousing 2|, the gasket receiving channel being disposed immediatelyabove the Joint at 33 between autoclave 33 and shaft housing 2|. Anannular metal gasket ring 33, rectangular in cross section, ispositioned on top of gasket 31. Annular retaining ring l8 threadedlyengages the top of'autoclave 33 at 34, the lower face of retaining ringI! being disposed immediately above the upper face of gasket ring 33when shaft'h'ousing 2| has been brought in closurecontact 'jwithautoclave 33 by the action of retaining ring 13 bearing againstanannular shoulder formed on shaft housing 2i at 3|. A plurality of boltsas at 38 pass through retaining ring l8 in threaded engagement therewithand bear against the upper face of gasket ring 33. A plurality ofsockets as at 35' are provided around the periphery of retaining ring Ifor the reception of a bar tool to assist in threading retaining ring |3into place.

Conduit 60 communicates from outside shaft housing 2| to the interior ofautoclave 33. An indirect heat transfer coil 5'1 is provided with aplurality of spacers as at 56 which also serve as baffles with respectto fluid materials contained within the autoclave. Coil 51 is in flowcommunication with conduit 60 through a pressure connection at 59,providing means for supplying a cooling or heating medium to coil 51. Anidentical conduit in shaft housing and pressure connection (not shown)are employed for fluid exitfrom coil 51.

Agitator shaft |9 extends to a point near the bottom of autoclave 33 andis provided at its termination with an inverted cup rigidly mountedthereon which partially'encloses filter 54. A plurality of agitatorblades as at 20 are also rigidly mounted on inverted cup 55 as shown.

Agitator shaft l9 extends through shaft housing 2|, an elongated sleeve63 being threaded into the bottom of shaft housing 2| and agitator shafti9 extending through sleeve 63. A graphite or other suitable bearing 62is provided between agitator shaft l9 and sleeve 33, cap 89 threaded onthe end of sleeve 63 serving to retain graphite bearing 62 in the end ofsleeve 83 as shown. Two sets of packing as at 65 and I3 separated by alantern ring 66, are provided above the end of sleeve 33. Packing gland14 bears against packing 13 and is secured by retainer 80 whichthreadedly engages the lower end of bearing Thus, the

housing 22. Lubricant is admitted to lantern ring 66 from reservoir 10via conduit 59, valve 33 and conduit 61. Conduit 12 leads from theinterior of autoclave 33 and is connected'with lubricant reservoir 10above the liquid level therein by' means of conduit 1|.

shaft housing 2| and sleeve 63 to communication with the space betweenagitator shaft I3 and sleeve 63. Since the tolerance between agitatorshaft l3 and graphite bearing 32 is not especially close, bearing 32serving primarily to steady the lower end of agitator shaft N, there is'a tendency for certain types of materials at times placed in theautoclave, particularly slurries of finely dividedpulverulent material,to work up between agitator shaft l9 and sleeve 63. In order to preventdamage to the shaft and the pressure packing under such conditions, aninert fluid or feed liquid or gas which is to be introduced into theautoclave may bepassed under pressure through conduit 34 and downbetween agitator shaft l3 and sleeve 63, thereby flushing this area andavoiding the undesirable conditions noted above.

Ball bearings as at 15 are provided in bearvas follows:

2,387,024 The autoclave is charged with the materials which are to beprocessed either by disconnecting the head closure and lowering theautoclave from the head or, alternatively, when freely flowing liquldsare to be charged, they may be passed through conduit 12 aftertemporarily removing threaded out of engagement with autoclave $3.

Carriage member 8, on which autoclave unit t is mounted by means ofsupport bracket 91, is then lowered by means of worm gear unit 95 androller chain Ill, counterweight It rising in column member. 2 ascarriage member 8 is lowered. If carriage member 3 is lowered until itrests on column flange 32, autoclave unit 8 will tilt to the positionshown in Figure II as the counterweight I3 is further raised by means ofworm gear unit 96, due to the weight of the autoclave unit and theoiicenter pivotal mounting of the autoclave unit on support bracket M at9.

If desired for any reason, the autoclave Jacket comprising outer shellor, inner shell t3 and insulators id, it and may be loweredindependently by loosening bolts 80, flange l9 and thermal insulators d8being lowered with the autoclave jacket as a unit and autoclave 33remaining at tached to shaft housing 2 l.

The autoclave is closed 'by raising autoclave unit 8 by means of wormgear unit 95 until autoclave 33 is firmly seated against shaft housingii at $39, corrugated gasketfll and gasket ring 38 are placed inposition and retaining ring it is threaded into autoclave 33 seated onthe shoulder of shaft housing 2!! at St. The final. pressure seal isthen made by tightening bolts 38. It

. will be seen that retaining ring it carries most of the pressure loadagainst the bottom of shaft housing 29 when the autoclave is underpressure, gasket 3'? being required only to prevent leakage around thejoint between autoclave 3t and shaft housing 21! at 39. Bolts 38 arethreadedly mounted in retaining ring it, bearing against gasket ring 35which in turn bears against gasket 39, and as a result are required toresist only the pressure load on the gasket.

This construction permits the use of much lighter and more easilysecured bolts than in the conventional autoclave closures wherein headbolts under tension load are required to resist the entirepressure loadon the closure. Furthermore, since the bolts in the present instanceareunder compression rather than tension load, the

failure of a bolt results in nothing more serious than slight leakagearound the gasket, whereas in conventional tension bolt closures,failure of one or more or the bolts often results in a serious explosionor at least flying metal fragments which endanger the operator.

With the autoclave closed and charged, heat may be applied to thecontents thereof either by clave is obtained through the action ofagitator blades in conjunction with bames 65 .mountstruction obviatesthe use of baiiles of one sort or another on the interior walls ofautoclave 33, the smooth walls of the present autoclave greatlyfacilitating cleaning operations and reducing initial constructioncosts. The pressure packing 65 and' 13 on the agitator shaft i9 isgravity lubricated, lubricant reservoir it being positioned at a higherlevel than the packing and the pressure above .the lubricant level inreservoir being equalized through conduits H and 12 which are infiowcommunication with the interior of autoclave St. The flow oflubricant to the packing is controlled by means of valve 68 betweenconduits 8i and 89.

The autoclave may be discharged either by lowering autoclave body 33from the head closure, as-described above with regard to the fillingoperation, or through discharge outlet W in those infiltration unitshown in Figure 111 is preferably employed and the autoclave dischargedby removing a valve normally provided in the threaded outlet end ofbushing hi, the filtrate passing through disc filter M, which may beadjusted by means of nut 88 as'hereinbefore detailed, through thegrooves in adjustment rod 83 and out through bushing M and the valve.The filtration may be carried out under the pressure existing inautoclave 33 after the processing of the contents has been completed, atatmospheric pressure by disconnecting conduit ill and permittingpressure equalization within the autoclave or by controlled pressurethrough conduit 72. Inverted cup member 55 which partially enclosesfilter M materially assists in the rapid and complete drainage of theautoclave, sincein the absence of this element the rate of dischargewould decrease as the liquid level in the autoclave fell below the topof filter 56 with consequent release of the gas pressure through the topof filter 56. In the structure shown, a siphon-like effect is attained,i. e. the liquid level within inverted cup 55 remains above the top offilter as until the liquid level in the autoclave falls below the lowerrim of inverted cup 55, thus utilizing the full filter surface untilvirtually all of the contents of the autoclave have carriage and vesselmay bereadily raised or loweredon said upright, and a closure for saidvessel mounted on said upright near the upper limit of travel of saidcarriage on said upright.

2. In an autoclave assembly, the combination comprising a supportupright, a pulley at the top 'of said upright, a carriage slidablymounted on said upright, a vessel pivotally and off center mounted nearthe bottom thereof on said carriage, a weight counterbalancing saidcarriage and vessel, flexible support means passing over said pulley andjoining said weight and said carriage, whereby said carriage and saidvesseled on and carried by heating coil 51. This conmay be readilyraised and lowered on said upright, and a closure for said vesselmounted near the top of said upright being positioned diametrically andvertically above said vessel on said carriage.

3. In an autoclave assembly, the combination comprising a supportupright, a carriage member slidably mounted on said upright, a vesselpivotally and oflcentr mounted near the base thereof on said carriagemember, a sprocket wheel rotatably mounted above said support upright,flexible support means passing over and engaging said sprocket wheel andsupporting said carriage member at one end and a counterweight disposedwithin said support upright at the other end, a closure for said vesselmounted on said upright near the upper limit oitravel of said carriagemember on said upright, a stop element mounted on said uprightandlimiting thelower limit of travel of said carriage member on saidupright, and means for rotating said sprocket wheel and thereby raisingand lowering said carriage member on said support upright.

4. In an autoclave assembly, the combination comprising a supportupright, a carriage member slidably mounted on said upright, a pressurevessel pivotally and oilcenter mounted near the base thereof onsaidcarriage member, a first sprocket wheel rotatably mounted above saidsupportupright, a second sprocket wheel rotatably mounted on saidcarriage member near the upper end thereof, a vertically adjustablecounterweight disposed within said upright support, flexible supportmeans attached to said counterweight at one end and to said carriagemember at the other end, said flexible support means passing over andengaging said first sprocket wheel and passing under and engaging saidsecond sprocket wheel, a closure for said vessel mounted on said uprightnear the upper limit of travel of said carriage member on said upright,a stop element mounted on said upright and limiting the lower limit oftravel of said carriage member on said upright and means forrotatingsaid firstsprocket wheel and thereby raising and lowering said carriagemember on said support upright.

5. In an autoclave, the combination comprising a pressure vesselincluding an opening therein, a closure element seating on an annularshoulder provided in said opening in said pressure vessel, anindependent closure retaining ring threadedly engaging said pressurevessel, said retaining ring being freely mounted on said closure elementand bearing against an annular shoulder provided on body'of saidpressure vessel, an agitator shaft rotatably mounted in said pressurevesseland extending downwardly into the body or said pressure vessel andan inverted cup element mounted on the end or said'agitator shaft andextending below the upper end of said filter element.

'7. In an autoclave, the combinationcomprisd log a pressure vesselincluding an opening and a discharge outlet therein,-closure meanssealing said opening in said pressure vessel, filter means 1 mounted insaid discharge outlet and extending upwardly within the body of saidpressure vessel, an agitator shaft rotatably mounted in said closuremeans and extending downwardly into said pressure vessel and an invertedcup element mounted on the end of said agitator shaft and extendingbelow the upper end of said filter element.

8. In an autoclave, the combination comprising a pressure vesselincluding a top opening and a bottom discharge outlet therein, closuremeans sealing said top opening in said pressure vesset,

. an agitator shaft rotatably mounted in said closure means andextending downwardly into the body of said pressure vessel, an invertedcup rigidly mounted on the lower end of said agitator shaft, 8. diskfilter mounted in said discharge outlet and extending upwardly into thebody of said pressure vessel and into said inverted cup, said diskfilter terminating above the lower rim of said inverted cup, anadjustment rod passing through said disk filter and means for adjustingthe compression exerted on said filter disk by said adjustment rod.

9.- In an autoclave, the combination comprising an open pressure vessel,closure means threadedly rigidly mounted on said agitator shaft abovesaid filter element and extending below the top of said filter element.

10. In an autoclave, the combination comprising an open pressure vessel,closure means threadedly engaging said pressure vessel, a pressuresealing gasket disposed between said closure means and said pressurevessel, means threadedly engaging said closure means urging said gasketdownwardly to form a pressure seal between said closure means and saidpressure vessel, annular heating means depending from said closuremeans, bame means mounted on said heating means, a pressure sealedagitator shaft rotatably mounted in said sealing means and extendingdownwardly into the both; of said pressure vessel, an agitator rigidlymounted on said agitator shaft, said agitator being disposed adjacentsaid bafie means mounted on said heating element. a

an inverted cup mounted on the end of said agitator shaft, a dischargeoutlet in said pressure vessel, and a filter element mounted in saiddischarge outlet extendingupwardly into the body of said pressure vesseland terminating within said inverted cup above the lower rim thereof.

11. In an autoclave, the combination comprising a pressure vesselincluding a top opening and,

a bottom discharge outlet therein, a closure ele ment seating on anannular shoulder provided in said top opening in said pressure vessel, aclosure retaining ring threadedly engaging said pressure asaigoes saidclosure element, a pressure sealing gasket covering the annular jointbetween-said closure element and said pressure vessel, a gasketretaining ring supported on said pressure gasket,

a plurality of bolts passing through said closure retaining ring inthreaded engagement therewith and urging said gasket retaining ringagainst said pressure gasket, thereby forming apressure seal betweensaid closure element and said pressure vessel, an annular heat exchangecoil depending from said closure element, the coils of said heatexchange coil being disposed adjacent the inner wall of said pressurevessel, means for circulating heat exchange media through said heatexchange coil, a pressure sealed agitator shaft rotatably mounted insaid closure element and extending within the body of said pressurevessel, an agitator rigidly mounted on said agitator shaft in saidpressure vessel, said heat exchange coil being disposed circumambientwith respect to at least a part of said agitator, a plurality ofvertical bafiies: mounted on said heat exchange coiladjacent saidagitator, an inverted cup rigidly mounted on said agitator andterminating immeately above said discharge outlet in said pressurevessel, a disk filter mounted in said discharge outlet and extendingupwardly into the body of said pressure vessel and into said invertedcup, thermal insulating means disposed around said pressure vessel andsupported by said pressure vessel and heating means disposed betweensaid thermal insulating means and said pressure vessel.

12. In an autoclave, the combination comprising an open pressure vessel,a plug closure there-

